1. Field of the Disclosure
The following disclosure generally relates to an image display apparatus and image display method and, more particularly, to an apparatus and method for preventing image display defects related to a noise occurrence.
2. Description of Related Art
Recently, various types of displays have become available on the market for displaying digital content. The most common displays are flat-panel type displays, such as, for example, Liquid Crystal Display (LCD) devices, Organic Light Emitting Display (OLED) devices, Light Emitting Display (LED) devices, and the like.
The vast majority of modern displays, including flat-panel type displays, include intra-panel interface technologies. Clock embedded signal technology typically includes sending both display data and clock information on a data transmission line to reproduce moving images on the displays. The clock information is associated with the data and embedded in the data signal to provide a clock embedded signal. Each pixel may be composed of three sub-pixels of Red, Green, and Blue. The data signal may include, for example, eight bits for each color data, totaling twenty-four bits for Red data, Green data, and Blue data for one pixel.
The displays typically include display driver integrated circuits (ICs) that control the display of images on the display screen by generating and supplying strobe signals (i.e. horizontal start signals) that are latched to a single horizontal line of the display screen. The display driver ICs typically include a data driver, a scan driver and a controller. The controller converts externally supplied digital display (or image) data to digital data that can be processed by the data driver; and, the controller supplies timing signals to control the data driver and scan driver to display the display data, including, among other things, strobe signals and a clock signals. The strobe signals are provided differently based on the resolution of the particular display device. In the case of a display device having a 1920×1080 resolution, the strobe signal is enabled 1080 times during a single image frame.
FIG. 1 shows an example of a driver timing chart for a single image frame. As seen in FIG. 1, the strobe signal is enabled for each scan line of the display (e.g., 1080 times for a single image frame) to scan all lines of the image frame. The strobe signal is generated automatically at a designated time, as seen in FIG. 1. The display driver IC includes a counter (not shown) that continuously counts and outputs an internal clock signal during the image display driving period, so that when all clock cycles of the internal clock signal configured to generate one scan line are completed, a strobe signal is automatically generated. This is the structure currently employed in most display driver ICs.
In FIG. 1, waveform A is a display data (or information) signal, waveform B is a strobe signal, and waveform C is a panel drive signal. Additionally, HBP stands for Horizontal Blanking Packet, which corresponds to the horizontal blanking section. The layout of a frame can be altered through the blanking section (or interval).
However, display driver ICs, like that described above, are susceptible to displaying erroneous data signals due to noise occurrences, such as, for example external noise occurrences. As discussed above, the display driver ICs generate strobe signals continuously in accordance with the horizontal line scan period, generating a strobe signal for every scan line in an image frame.
FIG. 2 shows an example where an external noise signal (e.g., electrostatic signal) is applied at point a, affecting the display driver IC. Referring to FIG. 2, after latching data of one scan line, a strobe signal is generated at point b even though the external noise signal was applied at point a. Since the noise signal occurred during data latch, an abnormal state is indicated and the clock signal and display data cannot be properly processed by the display driver IC. Thus, the display driver IC experiences a display defect, outputting the wrong display data during idle time until the clock signal and display data are restored to the normal state.
FIG. 3 illustrates an example of a display defect that is displayed on the screen of an image display device as an erroneous image on a horizontal line(s). Although FIG. 3 shows a single line defect, it is noted that most modern displays will generally produce defects across, for example, 3-5 scan lines of screen.